Measuring the long-term impact of the COVID-19 pandemic on HPV vaccination in Quebec, Canada: A cohort study from the Canadian immunization research network

OBJECTIVES: School-based vaccine programs in Quebec experienced significant disruptions due to the COVID-19 pandemic. Some vaccines offered in schools, such as the human papillomavirus (HPV) vaccine, continue to fall short of the 90% vaccine coverage (VC) target for the routine program. This study aims to assess temporal changes in VC for HPV, compare trends with other vaccines delivered in schools, and examine socioeconomic disparities in HPV VC. METHODS: We conducted a retrospective cohort study using data from the Quebec Immunization Registry linked with the Quebec Ministry of Education database to compare VC among students in Grades 4 and 9 between the 2019-2020 (pre-pandemic period) and the 2022-2023 school years (post-pandemic period). RESULTS: HPV VC ≥ 1 dose for students in Grade 4 declined in 2022-2023 (81.6%) compared with 2019-2020 (86.1%), with persistent inequalities among students living in the most deprived areas, as well as those from neighborhoods with higher proportions of immigrants or non-French/English language spoken at home. In 2022-2023, 90.7% of girls and 88.5% of boys in Grade 9 had received ≥ 1 dose of HPV vaccine. Compared with 2019-2020, VC among girls was 2 percentage points (pp) lower. No decline was observed for the hepatitis A and B vaccine in Grade 4 and the tetanus and diphtheria vaccine in Grade 9, but coverage for the Men-C-C vaccine in Grade 9 was 3.5 pp lower in 2022-2023. CONCLUSION: The decline in HPV VC has continued into 2022-2023, with persistent inequalities. Sustained efforts are needed to close the gap and ensure adequate protection.